Hi I have a requirement such that a a week should be ending on sunday. monday is the week start date. if a month start on sunday. then 2nd day of the month the monday will be in week 2 I need help in creating the week number ----- Thanks in Advance Arun -- View this message in context: http://r.789695.n4.nabble.com/Week-number-of-a-date-in-a-month-tp4554282p4554282.html Sent from the R help mailing list archive at Nabble.com.